In seven continuous tosses, Event X or Event Y appears randomly each time. If Event X appear first, then Event X appears the next time is 0.3. If Event Y appears first, then Event Y appears the next time is 0.4. If Event X appears in the fifth time, then what is the probability that Event X appears in the seventh time?
Give your answer as a fraction.

For a certain probability experiment, the probability that event A will occur is 1/2 and the probability that event B will occur is 1/3. Which of the following values could be the probability that the event A∪B (that is, the event A or B, or both) will occur?
Indicate all such values.

The probability that Event A occurs is 0.63, while the probability that Event B occurs is 0.58. What is the greatest probability that Event A and B both occurs?
Give your answer as a decimal.

The probability that Event A occurs is 0.45. What is the greatest possibility that Event A and Event B both occurs?
Give your answer as a decimal.

The probability that Event A occurs is 0.7, The probability that Event B occurs is 0.4. Which of the following could be the probability that Event A and B both occurs?
Indicate all such probabilities.

The probability that Event A occurs is 0.5, while the probability that Event B occurs is 0.3. What is the maximum possibility that both events do not occur?

If 125w + 25x + 5y + z = 264, and w, x, y and z are integers no less than 0 and no greater than 5, then the sum of w, x, y and z could be?
Indicate all such values
